Regular Expressions 101

This regexp can be used to validate domain names in Golang. While it cannot enforce the 253 character limit (with optional trailing period not included) that can be easily done by a simple len(domain) <= 253 check as well. This can be used as-is in other languages, even with RE2 regex engine. If po...

Notes: Do not forget to escape the $ by an additional $. Escaping ? like \? does not work. But you could use [?] instead End result should be like this: "traefik.http.middlewares.r6tt-dev-web.stripprefixregex.regex=^/[a-z0-9/]+[a-z0-9]+([?]+.*)?$$"...

Find all string matches with dir, one or more subdir, file name with optional extension. Common example with all capturing groups included: C://ProgramFiles/MyDir1/myDir2/file.ext

Find all string matches with dir, one or more subdir, file name with optional extension. Common example with all capturing groups included: ../../dir/SubDir1/SubDir2/file.ext ...

for quadratic equations ||ax^2+bx+c=d||

A regexp to validate an email address according to https://html.spec.whatwg.org/#valid-e-mail-address . Note that the backslash in the name part of the regexp on that site is there to escape the forward slash, which is not needed in Go.

Check golang for presence of utf-8 char in rawEmail e.g. ?= =?UTF-8?Q? or =?3D?UTF-8?Q?

Used in Traefik to add slash

Trying to adapt this regex to support LVM.

^(((\d{3}[1-9]|\d{2}[1-9]\d|\d[1-9]\d{2}|[1-9]\d{3})(\/)(((0[13578]|1[02])(\/)(0[1-9]|[12]\d|3[01]))|((0[469]|11)(\/)(0[1-9]|[12]\d|30))|(02(\/)(0[1-9]|[1]\d|2[0-8]))))|(((\d{2})(0[48]|2468|13579)|((0[48]|2468|3579)00))(\/)02(\/)29))$ Match year/month/day format. e.g: 2020/02/29 [match] 2021/02/29 ...

SQL comments on Big Query

This regex extracts Kubernetes Resource URIs. Copyright 2021 Mathew Wicks Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License....

nginx access log regex

11

Aquivalent solution for golang's unsupported negative lookahead in re2 flavor of go's regex. This example provides a negative lookahead similar to (?!/api/) ignoring routes with the /api/ prefix at the start.